C3 Tech Tip - Tachometer Needle Bouncing?
- Nov 5, 2013
Does the tachometer needle on your 1968-’74 bounce and not give a steady reading? Does your tachometer just not function? The tachometers on these Corvettes are cable driven from the distributor. The cable, like a speedometer cable, will wear and cause the needle to not hold steady because the cable ends are worn. Replacing the inner cable or the complete cable and casing will resolve this problem. For tachometers that do not work at all, it’s most likely because of the tachometer gear inside the distributor. You will need to remove the small bronze coupler on the side of the distributor and inspect both the small gear in the coupler as well as the distributor shaft. If the small gear shows signs of wear, then most likely the distributor main shaft will as well. Remove the distributor from the engine and replace the main shaft, small gear and coupler. There is a small plastic button inside the distributor that also would need replacing. Do the job once but do it right.
